JP2013235432A - Refrigerant circuit device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a refrigerant circuit device capable of preventing abnormal stop of a compressor due to overload even during high cooling load.SOLUTION: A refrigerant circuit device includes a refrigerant circuit 10 configured by connecting between: an in-chamber heat exchanger 24 that is installed in each of three or more commodity storage chambers 3 and evaporates a refrigerant subjected to adiabatic expansion in an expansion mechanism 23; a compressor 21 for compressing the refrigerant evaporated in the in-chamber heat exchanger 24; and an outside heat exchanger 22 for radiating heat of the refrigerant compressed by the compressor 21, by using a refrigerant pipeline 25. A fan control part 40 is also provided that performs total blast volume reduction control for reducing the total amount of blast volume of each in-chamber blast fan F1 while maintaining supply of the refrigerant into the in-chamber heat exchanger 24 in a case where an outside air temperature exceeds a standard outside air temperature, when the internal temperature of each commodity storage chamber 3 exceeds a set internal temperature, when the radiation temperature of the refrigerant in the outside heat exchanger 22 exceeds the set radiation temperature, or when rapid cooling operation is performed.

Description

  The present invention relates to a refrigerant circuit device, and more particularly to a refrigerant circuit device applied to, for example, a vending machine.

  2. Description of the Related Art Conventionally, as a refrigerant circuit device applied to, for example, a vending machine, one having a refrigerant circuit is known. As such a refrigerant circuit, a circuit having a cooling dedicated path and a heating path is known.

  The dedicated cooling circuit is configured by sequentially connecting an internal heat exchanger, a compressor, an external heat exchanger, and an expansion mechanism through a refrigerant pipe.

  The in-compartment heat exchanger is disposed inside the commodity storage of the vending machine. This internal heat exchanger cools the internal air (internal atmosphere) of the product storage, as the supplied refrigerant passes through a predetermined flow path and evaporates.

  The compressor is installed in the machine room inside the vending machine main body and outside the product container. The compressor sucks the refrigerant evaporated by the internal heat exchanger, compresses the sucked refrigerant, In this state, the liquid is discharged.

  The external heat exchanger is arranged in the machine room like the compressor, and introduces the refrigerant compressed by the compressor through the refrigerant pipe, and when the introduced refrigerant exchanges heat with ambient air and condenses. The ambient air is heated, that is, dissipates heat to the ambient air.

  The expansion mechanism is disposed in the machine room in the same manner as the compressor and the external heat exchanger, and decompresses the refrigerant condensed in the external heat exchanger to adiabatically expand.

  The heating path is a path including a heat exchanger for heating and a radiator. The heat exchanger for heating is arrange | positioned inside the goods storage. In more detail, it is arrange | positioned inside the goods storage container which accommodates the goods used as the heating object. In this heating heat exchanger, the inlet side is connected to a branch pipe branched from a refrigerant pipe connecting the compressor constituting the cooling exclusive path and the external heat exchanger. Such a heat exchanger for heating introduces a high-temperature and high-pressure refrigerant compressed by a compressor through a branch pipe, and the introduced high-temperature and high-pressure refrigerant exchanges heat with the low-temperature internal air of the product storage and condenses. It heats the air.

  The radiator is connected to the refrigerant pipe connected to the outlet side of the heat exchanger for heating and connected to the refrigerant pipe connecting the external heat exchanger and the expansion mechanism and connected to the refrigerant pipe. Is connected to the exit side. Such a radiator introduces the refrigerant condensed in the heat exchanger for heating, and heats the introduced refrigerant by exchanging heat with ambient air.

  In such a refrigerant circuit, a cooling electromagnetic valve and a heating electromagnetic valve are respectively provided in the refrigerant piping from the compressor to the external heat exchanger and the piping from the compressor to the heating heat exchanger. The cooling solenoid valve is opened when a cooling operation is performed to cool the internal atmosphere of all the product containers provided with the internal heat exchanger, and the refrigerant compressed by the compressor flows to the external heat exchanger. On the other hand, it is closed in the case of other operations, and the refrigerant compressed by the compressor is restricted from flowing to the external heat exchanger. On the other hand, the heating solenoid valve is opened when performing a heat pump operation that heats the internal atmosphere of one of the commodity containers provided with a heating heat exchanger and cools the internal atmosphere of the other commodity container, While the refrigerant compressed by the compressor is allowed to flow to the heating heat exchanger, it is closed in other operations, and the refrigerant compressed by the compressor is allowed to flow to the heating heat exchanger. It is something to regulate.

  When the cooling operation is performed, the refrigerant flows only through the cooling dedicated path, and when the heat pump operation is performed, the refrigerant flows through the heating path and a part of the cooling dedicated path (for example, Patent Document 1).

JP 2005-227833 A

  By the way, although not clearly shown in the above-mentioned Patent Document 1, the above refrigerant circuit device is a case where the internal air of all the product containers is cooled in a state where the outside air temperature is high, for example, in summer. When the cooling load of each product storage is large, that is, when the cooling load is high, the refrigerant sucked into the compressor, that is, the refrigerant returning from the internal heat exchanger to the compressor becomes high temperature. As a result, the compressor may stop abnormally due to overload.

  Therefore, in order to prevent the compressor from being overloaded, the refrigerant circulates only in the internal heat exchangers of some product storage units without simultaneously cooling the internal air of all the product storage units. It is possible to do.

  However, in the refrigerant circuit, the refrigerant filling amount is determined so that the internal air of all the product containers can be efficiently cooled, and the refrigerant circulates only to one internal heat exchanger at a high cooling load. In this case, the amount of refrigerant becomes excessive, leading to a reduction in efficiency due to an increase in high pressure in the refrigerant circuit, and as a result, the compressor may be abnormally stopped.

  In view of the above circumstances, an object of the present invention is to provide a refrigerant circuit device that can prevent a compressor from being abnormally stopped due to an overload even at a high cooling load.

  In order to achieve the above object, the refrigerant circuit device according to the present invention is disposed inside each of three or more target chambers, and is disposed by evaporating the refrigerant adiabatically expanded by the expansion mechanism. An internal heat exchanger that cools the internal atmosphere of the target chamber, a compressor that sucks and compresses the refrigerant evaporated in the internal heat exchanger, and introduces and condenses the refrigerant compressed in the compressor In the refrigerant circuit device including the refrigerant circuit configured by connecting the external heat exchanger with the refrigerant pipe, the internal atmosphere of the target chamber, which is provided inside the target chamber and is provided therein, is blown. When the internal air temperature of the target chamber exceeds a preset internal temperature when the outside air temperature exceeds the predetermined reference outside air temperature or the outside air temperature exceeds a preset reference outside temperature, or the refrigerant in the outside heat exchanger The heat dissipation temperature is When the set heat radiation temperature is exceeded, or when a rapid cooling operation for rapidly cooling the internal atmosphere of the target chamber is performed, the supply of the refrigerant to the internal heat exchanger is maintained while maintaining the supply of the refrigerant. And control means for performing total air flow reduction control for reducing the total air volume of the internal air blowing means.

  Further, in the refrigerant circuit device according to the present invention, the control unit drives the internal air blowing unit of the target chamber in which the internal temperature is most deviated from a predetermined reference internal temperature among the target chambers. The total air volume reduction control is performed by repeatedly stopping the air blowing means in the chamber of the target room.

  Further, according to the present invention, in the above refrigerant circuit device, the control unit drives the internal air blowing unit of the target chamber in which the internal temperature is most deviated from a predetermined reference internal temperature among the target chambers with the maximum output. The total air flow reduction control is performed by repeatedly driving the internal air blowing means of other target rooms with a minimum output.

  In the refrigerant circuit device according to the present invention, the refrigerant circuit includes a main path configured by connecting the internal heat exchanger, the compressor, and the external heat exchanger with a refrigerant pipe; The refrigerant compressed by the compressor is introduced and supplied to the heating heat exchanger disposed in the target chamber to be heated, and the refrigerant is condensed by the heating heat exchanger to be inside the target chamber. A high-pressure refrigerant introduction path for heating the atmosphere, and a return path for introducing the refrigerant condensed in the heating heat exchanger, supplying the refrigerant to the external heat exchanger, and returning it to the main path. To do.

  Further, in the refrigerant circuit device according to the present invention, the main path is formed by connecting a plurality of internal heat exchangers in series, and the refrigerant that has passed through one internal heat exchanger is heated in the other internal heat exchanger. It is characterized by passing through the exchanger.

  In the refrigerant circuit device according to the present invention, the expansion mechanism includes a valve that allows or regulates supply of the refrigerant to the internal heat exchanger on the upstream side of the internal heat exchanger, and the internal heat. It is arranged between the exchanger.

  In the refrigerant circuit device according to the present invention, carbon dioxide is used as the refrigerant.

  According to the refrigerant circuit device of the present invention, when the outside air temperature exceeds a predetermined reference outside air temperature, when each internal temperature of the target chamber exceeds a preset internal temperature, or in the outside heat exchanger When the heat radiation temperature of the refrigerant exceeds a preset heat radiation temperature, or when a rapid cooling operation for rapidly cooling the internal atmosphere of the target chamber is performed, the control means supplies the refrigerant to the internal heat exchanger. Since the total air volume reduction control is performed to reduce the total air volume of each of the internal air blowing means while maintaining the supply, the refrigerant sucked into the compressor, that is, the refrigerant returning from the internal heat exchanger to the compressor has a high temperature. Can be suppressed. Therefore, it is possible to prevent the compressor from being abnormally stopped due to overload even at a high cooling load.

FIG. 1 is a sectional view showing a case where an internal structure of a vending machine to which a refrigerant circuit device according to an embodiment of the present invention is applied is viewed from the front. FIG. 2 shows the internal structure of the vending machine shown in FIG. 1, and is a cross-sectional side view of the right commodity storage. FIG. 3 is a conceptual diagram conceptually showing the refrigerant circuit device according to the embodiment of the present invention. FIG. 4 is a block diagram showing a characteristic control system of the refrigerant circuit device according to the embodiment of the present invention. FIG. 5 is a conceptual diagram conceptually showing the refrigerant circuit device according to the embodiment of the present invention. FIG. 6 is a conceptual diagram conceptually showing the refrigerant circuit device according to the embodiment of the present invention. FIG. 7 is a flowchart showing the processing contents of the fan drive control processing performed by the fan control unit shown in FIG. FIG. 8 is a flowchart showing the processing contents of the supercooling load determination process in the fan drive control process shown in FIG. FIG. 9 is a flowchart showing the processing contents of the total air flow reduction control process in the fan drive control process shown in FIG. FIG. 10 is a flowchart showing the processing content of the release determination process in the total air flow reduction control process shown in FIG.

  DESCRIPTION OF EMBODIMENTS Hereinafter, preferred embodiments of a refrigerant circuit device according to the present invention will be described in detail with reference to the accompanying drawings as appropriate.

  FIG. 1 is a sectional view showing a case where an internal structure of a vending machine to which a refrigerant circuit device according to an embodiment of the present invention is applied is viewed from the front. The vending machine illustrated here includes a main body cabinet 1.

  The main body cabinet 1 has a rectangular shape with an open front surface. The main body cabinet 1 is provided with three independent commodity containers 3 partitioned by, for example, two heat insulating partition plates 2 in a side-by-side manner. This product storage 3 is for storing products such as canned beverages and beverages containing plastic bottles while maintaining a desired temperature, and has a heat insulating structure.

  FIG. 2 shows the internal structure of the vending machine shown in FIG. 1 and is a cross-sectional side view of the right product storage case 3. Here, the internal structure of the right product storage (hereinafter also referred to as right storage) 3a is shown, but the central product storage (hereinafter also referred to as intermediate storage) 3b and the left product storage (hereinafter referred to as right storage) 3a. The internal structure of 3c is also substantially the same as that of the right warehouse 3a. In the present specification, the right side indicates the right side when the vending machine is viewed from the front, and the left side indicates the left side when the vending machine is viewed from the front.

  As shown in FIG. 2, an outer door 4 and an inner door 5 are provided on the front surface of the main body cabinet 1. The outer door 4 is for opening and closing the front opening of the main body cabinet 1, and the inner door 5 is for opening and closing the front surface of the commodity storage 3. The inner door 5 is divided into upper and lower parts, and the upper door 5a opens and closes when a product is replenished.

  The product storage 3 is provided with a product storage rack 6, a carry-out mechanism 7 and a carry-out shooter 8. The commodity storage rack 6 is for storing commodities in a manner arranged in the vertical direction. The carry-out mechanism 7 is provided at the lower part of the product storage rack 6 and is used to carry out the products at the bottom of the product group stored in the product storage rack 6 one by one. The carry-out shooter 8 is for guiding the product carried out from the carry-out mechanism 7 to the product take-out port 4 a provided in the outer door 4.

  FIG. 3 is a conceptual diagram conceptually showing the refrigerant circuit device according to the embodiment of the present invention. The refrigerant circuit device illustrated here has a refrigerant circuit 10 in which carbon dioxide is enclosed as a refrigerant. The refrigerant circuit 10 includes a main path 20, a high-pressure refrigerant introduction pipe 30, and a return pipe 32. It is.

  The main path 20 is configured by sequentially connecting a compressor 21, an external heat exchanger 22, and an internal heat exchanger 24 through a refrigerant pipe 25.

  The compressor 21 is disposed in the machine room 9 as shown in FIG. The machine room 9 is a room inside the main body cabinet 1, partitioned from the product storage 3 and below the product storage 3. The compressor 21 sucks the refrigerant through the suction port, compresses the sucked refrigerant to be in a high-temperature and high-pressure state (high-pressure refrigerant), and discharges it from the discharge port.

  The compressor 21 in the present embodiment is a two-stage compressor that performs a compression operation in two steps, although not clearly shown in the figure. More specifically, the compressor 21 has a first compression element that performs a first compression operation and a second compression element that performs a second compression operation, and an intermediate heat exchanger is provided therebetween. It is. The intermediate heat exchanger dissipates the refrigerant compressed by the first compression operation by the first compression element and sends it to the second compression element.

  As shown in FIG. 2, the external heat exchanger 22 is disposed in the machine room 9 similarly to the compressor 21, and the first external heat exchanger 221 and the second external heat exchanger 222 are connected to each other. I have.

  When the refrigerant compressed by the compressor 21 passes through its own flow path, the first external heat exchanger 221 exchanges heat with ambient air to dissipate heat. A three-way valve 26 is provided in the refrigerant pipe 25 that connects the first external heat exchanger 221 and the compressor 21. The three-way valve 26 will be described later.

  The second external heat exchanger 222 is integrated with the first external heat exchanger 221 in a state where the fin member that is thermally connected to the flow path of the second external heat exchanger 222 is shared with the first external heat exchanger 221. It is structured. The second external heat exchanger 222 heats the refrigerant passing through the flow path, that is, the refrigerant dissipated by the first external heat exchanger 221 with heat exchange with ambient air.

  A plurality (three in the illustrated example) of the internal heat exchangers 24 are provided, and each of the internal heat exchangers 24 is disposed on the front side of the rear duct D in the low internal region of each commodity storage 3. The refrigerant piping 25 connecting the internal heat exchanger 24 and the second external heat exchanger 222 is branched into three by a distributor 27 disposed in the middle thereof, and disposed in the right warehouse 3a. Internal heat exchanger (hereinafter also referred to as a right internal heat exchanger) 24a, internal heat exchanger (hereinafter also referred to as an internal internal heat exchanger) 24b disposed in the internal storage 3b, and left storage 3c Are connected to the inlet side of the internal heat exchanger (hereinafter also referred to as the left internal heat exchanger) 24c.

  In the refrigerant pipe 25, electromagnetic valves 281, 282, and 283 are provided on the way from the distributor 27 to the internal heat exchangers 24. These solenoid valves 281, 282, and 283 are valve bodies that can be opened and closed. When an opening command is given from a control unit (not shown), the solenoid valves 281, 282, and 283 are opened to allow passage of the refrigerant while being given a closing command. In such a case, it is closed to restrict the passage of the refrigerant.

  Further, an expansion mechanism 23 is provided between the solenoid valves 281, 282, 283 and the internal heat exchangers 24 in the refrigerant pipes 25. As shown in FIG. 2, the expansion mechanism 23 is disposed inside each commodity storage 3 like the internal heat exchanger 24, and adiabatically expands by reducing the pressure of the refrigerant passing therethrough. The expansion mechanism 23 is constituted by, for example, a capillary tube.

  The refrigerant pipe 25 connected to the outlet side of the right-side heat exchanger 24a and the left-side heat exchanger 24c merges at the first joining point P1 in the middle and communicates with the suction port of the compressor 21. The compressor 21 is connected.

  In the main path 20, a refrigerant pipe (hereinafter also referred to as a connecting pipe) 25a connected to the outlet side of the internal heat exchanger 24b is connected to the refrigerant pipe 25 extending from the expansion mechanism 23 to the right internal heat exchanger 24a. The refrigerant pipe 25 is joined at a second joining point P2 on the way. That is, the main path 20 connects two in-compartment heat exchangers 24 that evaporate the supplied refrigerant in series by the connecting pipe (refrigerant pipe) 25a.

  One end of the high-pressure refrigerant introduction pipe 30 is connected to the three-way valve 26, and the other end is connected to the inlet side of the heat exchanger 31 for heating provided in the left warehouse 3c. The high-pressure refrigerant introduction pipe 30 introduces the refrigerant compressed by the compressor 21 and supplies the refrigerant to the heat exchanger 31 for heating. The refrigerant is condensed by the heat exchanger 31 for heating, and the internal air ( This constitutes a high-pressure refrigerant introduction path for heating the internal atmosphere. Here, the three-way valve 26 includes a first delivery state in which the high-pressure refrigerant compressed by the compressor 21 is delivered to the first external heat exchanger 221 and a second delivery state in which the high-pressure refrigerant is delivered to the heating heat exchanger 31. It is a valve that can be switched alternatively between. The switching operation of the three-way valve 26 is performed according to a command given from the control unit.

  The return pipe 32 has one end connected to the outlet side of the heating heat exchanger 31 and the other end connected to the refrigerant pipe 25 constituting the main path 20, that is, the first external heat exchanger 221 and the second external heat. The refrigerant pipe 25 is connected to the exchanger 222 at a third junction P3. The return pipe 32 constitutes a return path that introduces the refrigerant condensed in the heating heat exchanger 31 and supplies the refrigerant to the external heat exchanger 22 to return to the main path 20.

  In addition, the code | symbols H, 29, F1, and F2 in FIG. 3 are a heater, an internal heat exchanger, an internal fan, and an external fan, respectively. The heater H is a heating unit that is disposed in the middle store 3b and the left store 3c, and that heats the internal air of each of the middle store 3b and the left store 3c when driven and energized. The internal heat exchanger 29 exchanges heat between the high-pressure refrigerant that has passed through the second external heat exchanger 222 and the refrigerant that has passed through the internal heat exchanger 24 (low-pressure refrigerant). The internal blower fan F <b> 1 is disposed in the vicinity of the internal heat exchanger 24 inside each commodity storage 3, and is an internal blower that blows the internal air of the commodity storage 3 by driving. The outside blower fan F2 is disposed near the outside heat exchanger 22 and is a blower that blows air so as to pass outside air around the outside blower fan F2 when driven.

  FIG. 4 is a block diagram showing a characteristic control system of the refrigerant circuit device according to the embodiment of the present invention. As shown in FIG. 4, the refrigerant circuit device includes an outside air temperature sensor S <b> 1, an inside temperature sensor S <b> 2, a heat radiation temperature sensor S <b> 3, and a fan control unit 40.

  The outside air temperature sensor S1 is the outside air temperature of the vending machine to which the refrigerant circuit device is applied. More specifically, the outside air temperature is blown toward the outside heat exchanger 22 by driving the outside blowing fan F2 ( The outside air temperature) T is detected. The outside air temperature sensor S1 gives the detected outside air temperature T to the fan control unit 40 as a detection signal. The in-compartment temperature sensor S2 is disposed inside each commodity storage 3, and detects the in-compartment temperature (internal temperature) t1 of the commodity storage 3 in which it is disposed. These internal temperature sensors S2 give the detected internal temperature t1 to the fan control unit 40 as a detection signal. The heat radiation temperature sensor S3 detects the heat radiation temperature t2 of the refrigerant in the external heat exchanger 22 (the first external heat exchanger 221 in the present embodiment). This heat radiation temperature sensor S3 gives the detected heat radiation temperature t2 to the fan controller 40 as a detection signal.

  The fan control unit 40 controls the driving of the internal fan F1 according to programs and data stored in the memory 48, and includes an input processing unit 42, a determination processing unit 44, and a fan drive processing unit 46. is there. The fan control unit 40 may be configured integrally with a control unit that controls driving of the electromagnetic valves 281, 282, 283 and the three-way valve 26, or configured independently of such a control unit. It may be. In the present embodiment, the fan control unit 40 is configured independently of the control unit, and further configured independently of the vending machine control unit 50 that controls the sales operation of the vending machine. Will be described.

  The memory 48 stores reference outside air temperature information, set internal temperature information, set heat radiation temperature information, release temperature information, reference internal temperature information, and the like in addition to the above-described program.

  The reference outside air temperature information includes a reference outside air temperature Ts (for example, 38 ° C.) which is a precondition for determining the high cooling load state.

  The set internal temperature information includes a set internal temperature ti (for example, 20 ° C.) that serves as a threshold value for determining whether or not the product is in a high cooling load state based on the internal temperature in each commodity storage 3.

  The set heat radiation temperature information is used to determine whether or not a high cooling load state is based on the heat radiation temperature of the refrigerant in the external heat exchanger 22 (the first external heat exchanger 221 in the present embodiment). It includes a set heat radiation temperature tc that is a threshold value.

  The release temperature information includes a release temperature tic that is a threshold value for determining that the high cooling load state has been released based on the internal temperature in each commodity storage 3. The release temperature tic is a temperature lower than the set internal temperature ti.

  The reference internal temperature information includes a reference internal temperature determined in advance in each commodity storage 3, and this reference internal temperature may be determined for each commodity storage 3 or each commodity storage. It may be common to the storage 3. In the present embodiment, the reference internal temperature will be described as being the same as the set internal temperature ti and common to each commodity storage 3.

  The input processing unit 42 is used to input detection signals given from the sensors S1 to S3 every time a preset time elapses and to input a command from the vending machine control unit 50. The determination processing unit 44 determines whether or not the vehicle is in a high load cooling state based on the detection signal and command input through the input processing unit 42 and various temperature information read from the memory 48. The fan drive processing unit 46 individually drives or stops driving the internal fan F1 of each product storage case 3.

  The refrigerant circuit device having the above-described configuration cools or heats the product stored in the product storage 3 as follows.

  First, the case where CCC operation (operation which cools the internal air of all the goods storage 3) is performed is explained. In this case, the control unit sets the three-way valve 26 to the first delivery state, opens the electromagnetic valves 282 and 283, and closes the electromagnetic valve 281.

  As a result, the refrigerant compressed by the compressor 21 passes through the three-way valve 26 in the first delivery state and reaches the first external heat exchanger 221 as shown in FIG. The refrigerant that has reached the first external heat exchanger 221 performs heat exchange with ambient air (outside air) while passing through the first external heat exchanger 221 to radiate heat. The refrigerant dissipated in the first external heat exchanger 221 reaches the second external heat exchanger 222, exchanges heat with ambient air while passing through the second external heat exchanger 222, and further dissipates heat. The refrigerant that has dissipated heat in the second external heat exchanger 222 is branched by the distributor 27 through the internal heat exchanger 29 and is adiabatically expanded by the expansion mechanism 23 to be heat-exchanged in the internal storage 24b and the left-internal heat exchanger 24c. Then, each of the internal heat exchangers 24 evaporates and takes heat from the internal air of the commodity storage 3 to cool the internal air. The cooled internal air circulates in the interior by driving the internal blower fan F1, whereby the products stored in each product storage 3 are cooled to the circulating internal air.

  The refrigerant evaporated in the internal heat exchanger 24b passes through the connecting pipe 25a, reaches the upstream side of the right internal heat exchanger 24a, and evaporates in the right internal heat exchanger 24a. As a result, the internal air in the right warehouse 3a is cooled by the right internal heat exchanger 24a, and circulates in the interior by the drive of the internal air blower fan F1, whereby the products stored in the right warehouse 3a are circulated internal air. To be cooled.

  The refrigerant evaporated in the right-side heat exchanger 24a and the left-side heat exchanger 24c joins at the first junction P1, and then is sucked into the compressor 21 through the internal heat exchanger 29 and compressed by the compressor 21. Repeat the above cycle.

  Next, the case where the HCC operation (operation for heating the internal air of the left warehouse 3c and cooling the internal air of the middle warehouse 3b and the right warehouse 3a) is described. In this case, the control unit sets the three-way valve 26 to the second delivery state, opens the electromagnetic valve 282, and closes the electromagnetic valves 281 and 283.

  As a result, the refrigerant compressed by the compressor 21 passes through the three-way valve 26 in the second delivery state and is sent to the heating heat exchanger 31 through the high-pressure refrigerant introduction pipe 30 as shown in FIG.

  The refrigerant (high-pressure refrigerant) sent to the heat exchanger 31 for heating passes through a refrigerant passage (not shown), exchanges heat with ambient air (internal air), and condenses to heat the ambient air. The heated air circulates in the interior by driving the internal blower fan F1, so that the product accommodated in the left warehouse 3c is heated by the circulating air.

  The refrigerant that has passed through the heating heat exchanger 31 reaches the third junction P3 after passing through the return pipe 32, and enters the main path 20 at the third junction P3. The refrigerant that has entered the main path 20 radiates heat while passing through the second external heat exchanger 222 and then adiabatically expands in the expansion mechanism 23 via the internal heat exchanger 29 and the distributor 27.

  The refrigerant adiabatically expanded by the expansion mechanism 23 reaches the internal heat exchanger 24b, evaporates in the internal heat exchanger 24b, takes heat from the internal air of the internal chamber 3b, and cools the internal air. The cooled internal air circulates through the interior of the intermediate store 3b by driving the internal blower fan F1, thereby cooling the product accommodated in the intermediate store 3b.

  The refrigerant evaporated in the internal heat exchanger 24b passes through the connecting pipe 25a, reaches the upstream side of the right internal heat exchanger 24a, and evaporates in the right internal heat exchanger 24a. As a result, the internal air in the right warehouse 3a is cooled by the right internal heat exchanger 24a, and circulates in the interior by the drive of the internal air blower fan F1, whereby the products stored in the right warehouse 3a are circulated internal air. To be cooled.

  The refrigerant evaporated in the right-side heat exchanger 24a is sucked into the compressor 21 through the internal heat exchanger 29, is compressed by the compressor 21, and repeats the above-described circulation.

  When performing the above-described CCC operation, the fan controller 40 performs the following fan drive control process.

  FIG. 7 is a flowchart showing the processing content of the fan drive control processing performed by the fan control unit 40.

  When the outside air temperature T is input from the outside air temperature sensor S1 through the input processing unit 42 (step S100: Yes), the fan control unit 40 reads the reference outside air temperature information from the memory 48 through the determination processing unit 44, and the outside air temperature T The reference outside air temperature Ts included in the reference outside air temperature information is compared (step S200). When the outside air temperature T becomes equal to or lower than the reference outside air temperature Ts (step S200: No), the fan control unit 40 returns the procedure without performing the process described later, and ends the current fan drive control process.

  When the outside air temperature T is higher than the reference outside air temperature Ts (step S200: Yes), the fan control unit 40 performs a supercooling load determination process (step S300).

  FIG. 8 is a flowchart showing the processing contents of the supercooling load determination process in the fan drive control process shown in FIG.

  In this supercooling load determination process, when the fan control unit 40 inputs the internal temperature t1 from each internal temperature sensor S2 through the input processing unit 42 (step S301: Yes), the internal setting is made from the memory 48 through the determination processing unit 44. The temperature information is read, and all the internal temperatures t1 are compared with the set internal temperature ti (step S302).

  If all the internal temperatures t1 are higher than the set internal temperature ti (step S302: Yes), the fan control unit 40 determines that there is a supercooling load state through the determination processing unit 44 (step S303), and thereafter Return the procedure to end the current process.

  If all the internal temperatures t1 do not exceed the set internal temperature ti (step S302: No), the fan control unit 40 returns the procedure without determining that it is in the supercooling load state, and ends the current process.

  On the other hand, when the fan control unit 40 inputs the heat dissipation temperature t2 from the heat dissipation temperature sensor S3 through the input processing unit 42 without inputting the internal temperature t1 (step S301: No, step S304: Yes), through the determination processing unit 44. The set heat radiation temperature information is read from the memory 48, and the heat radiation temperature t2 is compared with the set heat radiation temperature tc (step S305).

  If the heat dissipation temperature t2 is higher than the set heat dissipation temperature tc (step S305: Yes), the fan control unit 40 determines that the supercooling load is in the determination processing unit 44 (step S306), and then returns the procedure. To end the current process.

  If the heat dissipation temperature t2 does not exceed the set heat dissipation temperature tc (step S305: No), the fan control unit 40 returns the procedure without determining that the supercooling load state is present, and ends the current process.

  Furthermore, the fan control unit 40 receives a rapid operation command from the vending machine control unit 50 through the input processing unit 42 without inputting the internal temperature t1 and the heat radiation temperature t2 (Step S301: No, Step S304: No, Step S307). : Yes), it is determined through the determination processing unit 44 that there is a supercooling load state (step S308), and then the procedure is returned to end the current process. Here, the rapid operation is referred to as so-called pull-down operation. After the outer door 4 and the inner door 5 are moved open to replenish products in the product storage rack 6 of each product storage 3, the outer door 4 and the inner door 5 are operated. In this operation, the door 5 is closed again to rapidly cool the internal air of each commodity storage 3.

  When none of the inside temperature t1, the heat radiation temperature t2, and the rapid cooling operation command is input (Step S301: No, Step S304: No, Step S307: No), the fan control unit 40 determines that the supercooling load state is present. Don't, return the procedure and end the current process.

  As a result of performing such a supercooling load determination process, when it is determined that the state is a supercooling load state (step S400: Yes), the fan control unit 40 performs a total air flow reduction control process (step S500). .

  FIG. 9 is a flowchart showing the processing contents of the total air flow reduction control process in the fan drive control process shown in FIG.

  In this total air flow reduction control process, the fan control unit 40 reads the internal temperature t1 from each internal temperature sensor S2 through the input processing unit 42 after a predetermined time has elapsed (step S501: Yes), and reads it from the memory 48. The reference internal temperature included in the reference internal temperature information is compared with the internal temperature t1, and the product storage 3 having the internal temperature most deviated from the reference internal temperature is determined (step S502, step S503, step S504). ). As described above, in the present embodiment, the reference internal temperature is the same as the set internal temperature ti and is common to each product storage 3, so that the internal temperature t 1 ( (Hereinafter also referred to as the internal temperature t1R of the right warehouse 3a, the internal temperature t1C of the central warehouse 3b, and the internal temperature t1L of the left warehouse 3c) The container 3 is determined.

  When the internal temperature t1R of the right chamber 3a is most deviated from the reference internal temperature (step S502: Yes, step S503: Yes), the fan control unit 40 sends the internal air of the right chamber 3a through the fan drive processing unit 46. The fan F1 (hereinafter also referred to as the right internal fan) F1 is driven, and the internal fan 3b (hereinafter also referred to as the internal fan) F1 and the left internal fan 3c (hereinafter referred to as the left) The driving of F1 (also referred to as an internal fan) is stopped (steps S505 and S506).

  When the internal temperature t1L of the left chamber 3c is most deviated from the reference internal temperature (step S502: Yes, step S503: NO, or step S502: No, step S504: No), the fan control unit 40 drives the fan. The left internal blower fan F1 is driven through the processing unit 46, and the right internal blower fan F1 and the central internal blower fan F1 are stopped (steps S507 and S508).

  When the internal temperature t1C of the internal storage 3b is most deviated from the reference internal temperature (step S502: No, step S504: Yes), the fan control unit 40 determines the internal internal blower fan F1 through the fan drive processing unit 46. Driving is performed to stop driving the right internal fan F1 and the left internal fan F1 (steps S509 and S510).

  After driving any one of the internal blower fans F1 in this way, the fan control unit 40 performs a release determination process (step S511).

  FIG. 10 is a flowchart showing the processing content of the release determination process in the total air flow reduction control process shown in FIG.

  In the release determination process, when the fan control unit 40 inputs the internal temperature t1 from each internal temperature sensor S2 through the input processing unit 42 after a predetermined time has elapsed (step S511a: Yes), the release temperature information read from the memory 48. Is compared with the internal temperature t1 (step S511b).

  When the internal temperature t1 (t1R, t1C, t1L) of all the product containers 3 is lower than the release temperature tic (step S511b: Yes), the fan control unit 40 sets the high cooling load state through the determination processing unit 44. It is determined that it has been removed, and a release determination is made (step S511c), after which the procedure is returned to end the current process.

  On the other hand, when the internal temperature t1 of all the product containers 3 is not lower than the release temperature tic (step S511b: No), the fan control unit 40 returns the procedure thereafter without performing the release determination, and performs the current process. Exit.

  By performing such a release determination process, the fan control unit 40 repeats the processes in steps S501 to S510 described above until a release determination is made (step S512: No). When the fan control unit 40 makes a release determination in the release determination process (step S512: Yes), the fan control unit 40 stops driving all the internal blower fans F1 through the fan drive processing unit 46 (step S513), and then performs the procedure. To finish the current total air flow reduction control process.

  The fan control part 40 which implemented this total ventilation volume reduction control process returns a procedure after that, and complete | finishes this fan drive control process.

  By performing this fan drive control process, even when the outside air temperature T exceeds the reference outside air temperature Ts, the inside temperature of each product storage case 3 can be sufficiently reduced, and the detection result of the inside temperature thereafter. Accordingly, it is possible to shift to a normal cooling operation in which the internal blower fan F1 is driven.

  As described above, according to the refrigerant circuit device of the present embodiment, when the outside air temperature T exceeds the reference outside air temperature Ts, when each inside temperature t1 exceeds the set internal temperature ti or the heat radiation temperature t2 When the set heat radiation temperature tc is exceeded, or when a rapid cooling operation command is given, it is determined that a high cooling load state is present. And when it is judged that it is in such a high cooling load state, while maintaining supply of the refrigerant to the internal heat exchanger 24, the internal temperature of the product storage 3 where the internal temperature t1 is most different from the reference internal temperature Since the air blower fan F1 is driven and the internal air blower fan F1 of the other product storage case 3 is repeatedly stopped to reduce the total amount of air blown by the air blower fan F1, the suction to the compressor 21 It can suppress that the refrigerant | coolant to be performed, ie, the refrigerant | coolant which returns to the compressor 21 from the internal heat exchanger 24, becomes high temperature. Therefore, it is possible to prevent the compressor 21 from being abnormally stopped due to overload even at a high cooling load.

  As described above, the compressor 21 can be prevented from abnormally stopping even under a high cooling load, and as a result, the internal air of each commodity storage 3 can be cooled well.

  The preferred embodiment of the present invention has been described above, but the present invention is not limited to this, and various modifications can be made.

  In the above-described embodiment, while the supply of the refrigerant to the internal heat exchanger 24 is maintained, the internal fan F1 of the product storage 3 in which the internal temperature t1 is most different from the reference internal temperature is driven. In the present invention, the total amount of air blown from the internal blower fan F1 is reduced by repeatedly stopping the internal blower fan F1 of the product storage box 3, but in the present invention, the internal heat exchanger 24 is used. While maintaining the supply of the refrigerant, the internal blower fan (internal fan means) F1 of the product storage (target chamber) 3 in which the internal temperature (internal temperature) t1 is most different from the reference internal temperature is maximized. Even if it drives and it repeats driving the internal ventilation fan (internal ventilation means) F1 of other goods storage (object room) 3 with the minimum output, and the total amount of the ventilation volume of the internal ventilation fan F1 is reduced. good. Also by this, it can suppress that the refrigerant | coolant sucked by the compressor 21, ie, the refrigerant | coolant which returns to the compressor 21 from the internal heat exchanger 24, becomes high temperature, and the compressor 21 also at the time of a high cooling load. Can be prevented from abnormally stopping due to overload.

  In the above-described embodiment, the main path 20 is configured by connecting the right internal heat exchanger 24a and the internal heat exchanger 24b in series by the connecting pipe 25a, and the internal heat exchanger 24b is connected to the internal heat exchanger 24b. The refrigerant that has passed passes through the right internal heat exchanger 24a. However, in the present invention, the right internal heat exchanger 24a and the internal internal heat exchanger 24b are connected in series by the connecting pipe 25a. It may be a refrigerant circuit in which the internal heat exchangers are connected in parallel.

  In the above-described embodiment, since the reference internal temperature is common to each product storage 3 in the total air flow reduction control process, the internal temperature t1 of each product storage is compared, and the internal temperature In the present invention, when the reference internal temperature is individually determined for each target room (commodity storage 3), the commodity storage 3 where t1 is most deviated from the reference internal temperature is determined. The difference between the internal temperature of the target room and the reference internal temperature is obtained for each target room, and the target room where the internal temperature is most different from the reference internal temperature is determined.

DESCRIPTION OF SYMBOLS 10 Refrigerant circuit 20 Main path | route 21 Compressor 22 External heat exchanger 221 1st external heat exchanger 222 2nd external heat exchanger 23 Expansion mechanism 24 Internal heat exchanger 25 Refrigerant piping 27 Distributor 30 High pressure refrigerant introduction Piping 31 Heat exchanger for heating 32 Return path 40 Fan control unit 42 Input processing unit 44 Judgment processing unit 46 Fan drive processing unit 48 Memory 50 Vending machine control unit F1 Internal blower fan F2 External blower fan S1 Outside air temperature sensor S2 Inside Temperature sensor S3 Heat dissipation temperature sensor

Claims (7)

An internal heat exchanger that cools the internal atmosphere of the target chamber in which the refrigerant is disposed by evaporating the refrigerant that is disposed in each of the three or more target chambers and is adiabatically expanded by the expansion mechanism;
A compressor that sucks and compresses the refrigerant evaporated in the internal heat exchanger;
In a refrigerant circuit device including a refrigerant circuit configured by connecting a refrigerant compressed by the compressor and dissipating heat from an external heat exchanger connected by a refrigerant pipe,
In-compartment blowing means for blowing the internal atmosphere of the target chamber provided inside each of the target chambers and provided therein,
When the outside air temperature exceeds a predetermined reference outside air temperature, when the internal temperature of each of the target chambers exceeds a preset internal temperature, or the heat release temperature of the refrigerant in the external heat exchanger is preset. When the set heat radiation temperature is exceeded, or when a rapid cooling operation for rapidly cooling the internal atmosphere of each of the target chambers is performed, the internal ventilation is maintained while maintaining the supply of the refrigerant to the internal heat exchanger. And a control means for performing total air volume reduction control for reducing the total air volume of each means.   The control means drives the internal air blowing means of the target room in which the internal temperature is most deviated from a predetermined reference internal temperature, and stops driving the internal air blowing means of the other target rooms. The refrigerant circuit device according to claim 1, wherein the total air flow reduction control is performed by repeating the operation.   The control means drives the internal air blowing means of the target room where the internal temperature is most different from a predetermined reference internal temperature among the target rooms at a maximum output, and the internal air blowing means of the other target chambers. The refrigerant circuit device according to claim 1, wherein the total air blowing amount reduction control is performed by repeatedly driving with a minimum output. The refrigerant circuit is
A main path configured by connecting the internal heat exchanger, the compressor, and the external heat exchanger with a refrigerant pipe;
The refrigerant compressed by the compressor is introduced and supplied to the heating heat exchanger disposed in the target chamber to be heated, and the refrigerant is condensed by the heating heat exchanger to be inside the target chamber. A high-pressure refrigerant introduction path for heating the atmosphere;
A return path that introduces a refrigerant condensed in the heat exchanger for heating, supplies the refrigerant to the external heat exchanger, and returns the refrigerant to the main path is provided. The refrigerant circuit device according to one.   The main path is formed by connecting a plurality of internal heat exchangers in series, and the refrigerant that has passed through one internal heat exchanger passes through the other internal heat exchanger. The refrigerant circuit device according to claim 4.   The expansion mechanism is disposed between the internal heat exchanger and a valve that allows or regulates supply of the refrigerant to the internal heat exchanger on the upstream side of the internal heat exchanger. The refrigerant circuit device according to any one of claims 1 to 5.   The refrigerant circuit device according to any one of claims 1 to 6, wherein carbon dioxide is used as the refrigerant.

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